Donald Trump is getting “nuttier and nuttier,” according to those within the tycoon’s presidential campaign, who say they are increasingly frustrated by his outrageous comments and behavior.

The Republican candidate has been engaged in a prolonged war of words with Khizr and Ghazala Khan — whose son, a US Army officer, was killed in Iraq in 2004 — which many inside the presidential campaign see as, at the very least, a total distraction.

“I did not think he’d be great in a general election, and thought there’d be episodes of paranoia/irrationality, but this is surprising for me,” one Trump operative told The Post.

“Trump is getting nuttier and nuttier,” the person added.

Campaign chairman Paul Manafort and other staffers “feel like they are wasting their time,” CNN reported Wednesday.

Campaign aides wish Trump were spending more time talking about public policy and aiming his fire at Hillary Clinton.